Sleep study in patients with overweight and obesity

Obstructive sleep apnea syndrome (OSAS) is a disorder characterized by repetitive collapse of the pharyngeal airway during sleep, which leads to oxygen desaturation, sleep fragmentation and daytime somnolence. Obesity is one of the most important risk factor for the development of OSAS. The exact mechanisms responsible for the relationship between obesity and OSAS are still unclear. The fat deposits in the pharynx region as well as the reduction in the lung volume have been considered as factors that might be responsible for the increase of the upper airway collapsibility. The aim of our study was to evaluate the correlation between the Body Mass Index (BMI) and sleep study parameters in overweight and obese patients suffering from breathing disturbances during sleep. We studied a group of 106 consecutive obese or overweight patients with a primary complaint of snoring or other breathing disturbances during sleep. In all cases, BMI and sleep studies (PolyMESAM) were examined. We evaluated relationship between the BMI and sleep study parameters such as Respiratory Disturbance Index (RDI), Apnea Index (AI), Desaturation Index (DI) and Average of Lowest Saturation (LSAT). The results showed the lack of significant statistical correlations between BMI and all the sleep parameters studied in the overweight patients and the statistical positive correlation between the BMI and RDI in the obese cases. We conclude that BMI determination may be considered as a simple, yet important predictor, of the OSAS in the group of obese patients.